This invention relates to improved flexible laminated structures having superabsorbent material incorporated therein. It relates particularly to laminated structures in which the superabsorbent material is provided as discrete chunks or pieces of superabsorbent element frictionally secured to a porous support layer.
Commercial superabsorbent materials most often are provided in the form of fine powders which have been incorporated into absorbent fibrous webs, as disclosed by U.S. Pat. No. 4,500,315 to Pieniak et al. However, it has been found that when such powders are incorporated in a fibrous web, they tend to sift out of the web during handling. On the other hand, superabsorbent materials provided in the form of continuous film or sheets, tend to be undesirably stiff and difficult to use in absorbent products. A variation on the use of films is to spread superabsorbent material on the surface of a porous material such as a fiber web, but the resulting web is also very stiff. Thus, it would be desirable to provide an absorbent structure containing superabsorbent material which overcomes both of these problems. These disadvantages of the prior art absorbent web structures have led to the development of the improved superabsorbent laminated structure of the present invention, in which superabsorbent material is provided as discrete elements frictionally attached to a flexible porous support layer.